Smart contracts on Ethereum are fully self contained and any information or access to off-chain data is restricted. Tellor solves this problem by creating a system where parties can request the value of an off-chain data point (e.g. ETH/USD) and miners compete to add this value to an on-chain data bank, accessible by all Ethereum smart contracts. Inputs to a data series are secured by a network of staked miners. The main Tellor smart contract creates a time series of each requested data series and aims to become the standard source of high value data for decentralized applications. This oracle, “Tellor”, utilizes similar incentive mechanisms to other cryptocurrency systems through the issuance of Tellor’s token, Tributes, that are used to request a particular data series from miners.
Solarcoin is a Scrypt based alternative digital currency and its innovation comes from the secondary proof of work reward: the Solar Proof of Work. Green solar energy producers are entitled to receive one SLR for every MWh electricity generated. In order to claim a Solar Proof of Work reward, solar plant owners must submit 3rd party verified energy generation certificates such as a Solar Renewable Energy Certificate (SREC) or equivalent country specific documentation. All Solar Proof Of Work rewards will be stored as transactions in the blockchain. The supply of SLR comprises of the following: - The Mining Pool: 105 million Solarcoins (0.1%) to be publicly mined over the next 40 years. All publicly mined Solarcoins represent historically generated and unclaimed solar electricity. - The Generator Pool: 97.5 billion SolarCoins (99.4%) are currently stored in the OCA non-circulating generation pool account. These will be exchanged for Solar Proof of Work claims of solar electricity generation submitted over the next 40 years at the rate of 1 SLR per MWh of solar energy. - The Genesis Pool: 500 million Solarcoins (0.5%) are stored in the genesis pool account for environmental charities, early volunteers, advisers, builders and maintainers of SolarCoin infrastructure. Genesis pool circulation is capped so that it will never represent more than 5% of total Solarcoin in circulation.